no nfl logos on it. nothing to say it's an official product. >> reporter: so what makes sports merchandise official? well, a hologram, tags, a higher price, and the fact that the nfl gets a cut, about $1.50 on every $30 t-shirt money split between all 32 franchises. >> super bowl shirts here! >> reporter: so while you may be saving on the knockoff you're not necessarily supporting your team and considering the quality, you may end up paying more in the long run. >> downside is you're not getting a genuine product. the quality is probably not good. there may be chemicals that are not approved to be used. >> reporter: counterfeit shirts can also have misspellings. we bought one that came complete with a stain. it is illegal to buy a counterfeit in some cities if you know it's a counterfeit. so buyer beware. a good hunch is that it's pretty cheap. in looking at it, too, the official tags have the holograms. you can really tell now that we have these side by side which is fake and which is real -- what we be